Cool roof waterproofing
In 2025, Cool roof waterproofing was made with Impermax ST.
01 · Project overview
What is this project?
In 2025, Cool roof waterproofing was made with Impermax ST.
This one is a cool roof.
Impermax goes on cold, by roller or spray, normally in two coats.
The system named for this job is R Proof PU COOL ROOF.
Krypton Chemical makes the resin. The crew on site applies it. On Cool roof waterproofing the details have to get the same film as the open field, and the cure has to finish before the building goes back to work.
| Project | Cool roof waterproofing |
|---|---|
| Year | 2025 |
| Line | Waterproofing |
| Products | Impermax ST |
02 · The challenge
What did this structure ask of the system?
Cool roof waterproofing has to do two jobs. It keeps the rain out, and it keeps the heat of the sun off the rooms underneath. A dark membrane in full sun becomes a radiator. A light, reflective face is part of the waterproofing, not a paint added for looks.
The deck still moves between afternoon and night. The membrane has to stretch with it, and the outlets and parapets have to be in the same film. A cool roof that is thin at the edge leaks, however white the middle is.
03 · The solution
Which system was trusted here?
The system trusted here is the one named for the job: Impermax ST. It is chosen because it matches the substrate and the exposure, not because every building wants the same can.
On a roof the membrane has to follow outlets and upstands at the same thickness as the field. An exposed aromatic film takes a topcoat if the colour will be seen.
04 · Application
How is the system built?
Impermax is the cold liquid polyurethane. Stir it slowly, let the bubbles rise, and lay it by roller, brush or airless spray. Two coats in different colours, about 1 kg per square metre each, make the coverage obvious. A spiked roller knocks bubbles down while the film is wet. Outlets, upstands and cracks are detailed first. Keep the deck between 5 and 40 degrees C, and keep it dry.
On a warm day a coat is walkable in one or two days. About 90 percent of final properties arrive in three days, and full hardness takes 10 to 15 days. Wait that long before the surface is held under water. Typical elongation is 450 to 600 percent. The resin is aromatic, so a roof left in the sun is given an aliphatic topcoat if the colour has to stay true. Again, these are datasheet figures, not a reading taken on Cool roof waterproofing.
On Cool roof waterproofing the roof fails at the edge long before it fails in the field. Parapets, outlets, plant plinths and laps are detailed first, with the same system, at the same thickness. A bay can be perfect and the ceiling still stains if the outlet was a collar of mastic.
The deck moves between the hot afternoon and the night. The membrane has to move with it. A rigid coat maps every crack in the substrate onto the ceiling. Thermal movement is the reason an elastic system is on a roof like this, not a preference for a particular can.
Where the film stays in the sun, colour and waterproofing are two layers. The membrane keeps the water out. An aliphatic coat keeps the appearance. Skipping the topcoat because the membrane is already waterproof is how a sound roof starts to look failed, and then gets recoated for the wrong reason.
05 · Results
What does a job like this stand behind?
Cool roof waterproofing has one standard. The coating is still doing its job after the building is back in use, at the details as well as in the middle.
Figures for cure, thickness and strength, where they are given, come from the product data sheets. They are not a test cut out of this building.
What this asks of Cool roof waterproofing is workmanship at the difficult line. The open field is the easy part of a resin job. Outlets, edges, penetrations and changes of plane are where thickness goes missing, and where water or wear finds the gap. The same products and the same care belong there, and the cure is allowed to finish before the building goes back into use. That is the difference between a coating that was simply applied and a system that stays in service.
06 · Products
Products on this job
Impermax ST
Named on this project. The data sheet carries the application window and the typical figures.
07 · FAQ
Frequently asked questions
Where is this project?
Cool roof waterproofing. the place named on this project
When was the work done?
2025.
Which products were used?
Impermax ST.
Why are the details done first?
Outlets, upstands and joints are where water gets in. They are closed with the same system as the main area.
Where do the cure times come from?
From the product data sheet. They describe the resin, not a clock stopped on this site.
The programme does not change because the building is smaller or further away. Prepare the substrate until it will hold the system, close the details before the field, and keep the thickness honest at every edge. A second visit to repair a starved detail costs more than doing that detail on the first day. Cool roof waterproofing is held to that standard. Krypton Chemical supplies the resin. The applicator owns the surface.